CN215576627U

CN215576627U - Fingerprint sensor housing having non-uniform thickness

Info

Publication number: CN215576627U
Application number: CN202120723345.5U
Authority: CN
Inventors: 谭业成; 文声敏
Original assignee: Synaptics Inc
Current assignee: Synaptics Inc
Priority date: 2020-06-23
Filing date: 2021-04-09
Publication date: 2022-01-18
Anticipated expiration: 2031-04-09
Also published as: CN113836989A; US20230206683A1; US20210397809A1; US11625945B2; US12026971B2

Abstract

A sensor assembly includes a cover layer and a first sensor device. The cover layer is molded from a first material to have a flat surface and a non-uniform thickness, wherein the thickness of the first material at a first region of the cover layer is less than the thickness of the first material surrounding the first region. In the first region, a first sensor device is arranged below the flat surface of the cover layer. The first sensor arrangement is configured to transmit and receive a first capacitive sensing signal through a portion of the planar surface coinciding with the first area. For example, the first sensor device may be a fingerprint sensor configured to detect a fingerprint on the portion of the flat surface coinciding with the first area based on a change in the first capacitive sensing signal.

Description

Fingerprint sensor housing having non-uniform thickness

Technical Field

The present embodiments relate generally to fingerprint sensors and, in particular, to fingerprint sensor housings having non-uniform thicknesses.

Background

Authentication is a mechanism for verifying the identity of a user attempting to access a device and/or application. A basic form of authentication may require a user to enter a username and password via an input device. However, usernames and passwords are easily stolen and can be used by unauthorized users to gain access to corresponding devices or applications. Accordingly, modern authentication schemes increasingly rely on biometric sensors (e.g., sensors capable of identifying a user's unique biometric characteristics) to provide a higher level of security. Example biometric sensors include fingerprint scanners, facial recognition systems, eye scanners, voice recognition systems, and the like. Biometric input typically requires a user to physically interact with one or more sensors to perform authentication.

Some fingerprint scanners may use capacitive imaging techniques to capture the details of a user's fingerprint. For example, a fingerprint scanner may include an array of capacitive sensing elements (e.g., sensor electrodes) for measuring changes in capacitance or electric field on a fingerprint sensing surface produced by a finger interacting with the surface. More specifically, the amount of charge accumulated on the capacitive sensing element may be related to ridges and valleys in the user's fingertip. To ensure a high level of detail and accuracy in the capacitive measurements required for fingerprint authentication, the fingerprint sensing surface is typically formed by placing a very thin sheet of cover material (such as glass) over the capacitive sensing elements. However, such cover sheets are fragile, expensive to manufacture, and provide limited customizability.

SUMMERY OF THE UTILITY MODEL

This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

One innovative aspect of the presently disclosed subject matter can be embodied in a sensor assembly that includes a cover layer and a first sensor arrangement. The cover layer is molded from a first material to have a flat surface and a non-uniform thickness, wherein the thickness of the first material at a first region of the cover layer is less than the thickness of the first material surrounding the first region. Within the first zone, a first sensor arrangement is disposed below the planar surface of the cover layer and is configured to transmit and receive a first capacitive sensing signal through a portion of the planar surface coinciding with the first zone.

Another innovative aspect of the presently disclosed subject matter can be realized in a method of manufacturing a sensor assembly. The method comprises the following steps: molding a first material to form a cover layer having a flat surface and a non-uniform thickness, wherein a thickness of the first material at a first region of the cover layer is less than a thickness of the first material surrounding the first region; and disposing a first sensor arrangement below the planar surface of the cover layer within the first region, wherein the first sensor arrangement is configured to transmit and receive a first capacitive sensing signal through a portion of the planar surface that coincides with the first region.

Another innovative aspect of the presently disclosed subject matter can be embodied in a sensing assembly that includes an overlay, a fingerprint sensor, and a proximity sensor. The cover layer is molded from a first material to have a flat surface and a non-uniform thickness, wherein the thickness of the first material at a first region of the cover layer is less than the thickness of the first material surrounding the first region. Within the first zone, a fingerprint sensor is disposed below the flat surface of the cover layer and is configured to detect a fingerprint on a portion of the flat surface coinciding with the first zone. In a second region surrounding the first region, a proximity sensor is disposed below the planar surface of the cover layer and is configured to detect a position of the input object relative to a portion of the planar surface that coincides with the second region.

Drawings

The present embodiments are illustrated by way of example and not intended to be limited by the figures of the accompanying drawings.

FIG. 1 shows an example input device that can be used with the present embodiments.

Fig. 2A and 2B illustrate an example sensor assembly according to some embodiments.

Fig. 3A-3C illustrate cross-sectional views of an example sensor assembly at various stages of a manufacturing process, according to some embodiments.

Fig. 4A and 4B illustrate another example sensor assembly according to some embodiments.

Fig. 5A and 5B illustrate another example sensor assembly according to some embodiments.

Fig. 6A and 6B illustrate another example sensor assembly according to some embodiments.

FIG. 7 illustrates another example input device that may be used with the present embodiments.

Fig. 8A and 8B illustrate another example sensor assembly according to some embodiments.

9A-9F illustrate cross-sectional views of another example sensor assembly at various stages of a manufacturing process, according to some embodiments.

FIG. 10 shows an illustrative flow diagram of a process for manufacturing a sensor assembly, according to some embodiments.

Detailed Description

In the following description, numerous specific details are set forth, such as examples of specific components, circuits, and processes, in order to provide a thorough understanding of the present disclosure. The term "coupled," as used herein, means directly connected to or connected through one or more intermediate components or circuits. The terms "electronic system" and "electronic device" may be used interchangeably to refer to any system capable of electronically processing information. Furthermore, in the following description and for purposes of explanation, specific nomenclature is set forth to provide a thorough understanding of the various aspects of the disclosure. However, it will be apparent to one skilled in the art that these specific details may not be required in order to practice the example embodiments. In other instances, well-known circuits and devices are shown in block diagram form in order to avoid obscuring the present disclosure. Some portions of the detailed descriptions which follow are presented in terms of procedures, logic blocks, processing, and other symbolic representations of operations on data bits within a computer memory.

These descriptions and representations are the means used by those skilled in the data processing arts to most effectively convey the substance of their work to others skilled in the art. In the present disclosure, a process, logic block, process, etc., is conceived to be a self-consistent sequence of steps or instructions leading to a desired result. The steps are those requiring physical manipulations of physical quantities. Usually, though not necessarily, these quantities take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared, and otherwise manipulated in a computer system. It should be borne in mind, however, that all of these and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities.

Unless specifically stated otherwise as apparent from the following discussions, it is appreciated that throughout the present application, discussions utilizing terms such as "accessing," "receiving," "sending," "using," "selecting," "determining," "normalizing," "multiplying," "averaging," "monitoring," "comparing," "applying," "updating," "measuring," "deriving," or the like, refer to the action and processes of a computer system, or similar electronic computing device, that manipulates and transforms data represented as physical (electronic) quantities within the computer system's registers and memories into other data similarly represented as physical quantities within the computer system memories or registers or other such information storage, transmission or display devices.

In the drawings, a single block may be described as performing one or more functions; however, in actual practice, one or more functions performed by the block may be performed in a single component or across multiple components, and/or may be performed using hardware, using software, or using a combination of hardware and software. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described below generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention. Further, example input devices may include components in addition to those shown, including well-known components such as processors, memories, and the like.

The techniques described herein may be implemented in hardware, software, firmware, or any combination thereof, unless explicitly described as being implemented in a particular manner. Any features described as modules or components may also be implemented together in an integrated logic device or separately as discrete but interoperable logic devices. If implemented in software, the techniques may be realized at least in part by a non-transitory processor-readable storage medium comprising instructions that, when executed, perform one or more of the methods described above. The non-transitory processor-readable data storage medium may form part of a computer program product, which may include packaging materials.

The non-transitory processor-readable storage medium may include Random Access Memory (RAM), such as Synchronous Dynamic Random Access Memory (SDRAM), Read Only Memory (ROM), non-volatile random access memory (NVRAM), Electrically Erasable Programmable Read Only Memory (EEPROM), flash memory, other known storage media, and the like. Additionally or alternatively, the techniques may be realized at least in part by a processor-readable communication medium that carries or communicates code in the form of instructions or data structures and that can be accessed, read, and/or executed by a computer or other processor.

The various illustrative logical blocks, modules, circuits, and instructions described in connection with the embodiments disclosed herein may be executed by one or more processors. The term "processor" as used herein may refer to any general purpose processor, conventional processor, controller, microcontroller, special purpose processor, and/or state machine capable of executing scripts or instructions of one or more software programs stored in memory.

Various embodiments are generally directed to an input device capable of fingerprint sensing. Some embodiments more particularly relate to a fingerprint sensor assembly having an input surface and a housing formed from a single layer of dielectric material. In some embodiments, the sensor assembly may include a cover layer and a first sensor device. The cover layer is molded from a first material (such as plastic, mylar, or polymer) having a flat surface and a non-uniform thickness, wherein the thickness of the material at the first region of the cover layer is less than the thickness of the material surrounding the first region. Within the first zone, a first sensor arrangement is disposed below the planar surface of the cover layer and is configured to transmit and receive a first capacitive sensing signal through a portion of the planar surface coinciding with the first zone. In some other embodiments, a second sensor arrangement may be provided below the planar surface of the cover layer in a second region surrounding the first region and configured to transmit and receive a second capacitive sensing signal through a portion of the planar surface coinciding with the second region.

Particular embodiments of the subject matter described in this disclosure can be implemented to realize one or more of the following potential advantages. In some implementations, the described techniques may be used to manufacture low cost fingerprint sensor assemblies that provide robust performance and user experience. For example, by molding the input surface and housing from a single layer of material, the manufacturing and assembly process can be streamlined and the associated costs are reduced. By using a plastic or polymer material for the cover layer, the input surface can be made very thin while maintaining a relatively high dielectric constant, thus improving the performance of the fingerprint sensor. Furthermore, by combining the fingerprint sensor with an additional sensor device (such as a proximity sensor) underneath the same cover layer, the sensor arrangement may provide a continuous or uninterrupted input surface capable of receiving multiple forms of user input. The continuous input surface may improve the user experience while reducing or eliminating "dead zones" at transitions or intersections between the fingerprint sensor and the additional sensor device.

FIG. 1 shows an example input device 100 that can be used with the present embodiments. The input device 100 includes a processing system 110 and a sensing region 120. In some embodiments, input device 100 may be configured to provide input and/or control access to an electronic system (not shown for simplicity). Example electronic systems may include, but are not limited to, personal computing devices (e.g., desktop computers, laptop computers, netbook computers, tablet computers, web browsers, e-book readers, Personal Digital Assistants (PDAs), etc.), composite input devices (e.g., physical keyboards, joysticks, key switches, etc.), data input devices (e.g., remote controls, mice, etc.), data output devices (e.g., display screen printers, etc.), remote terminals, kiosks, video game consoles (e.g., video game consoles, portable game devices, etc.), communication devices (e.g., cellular telephones, smart phones, etc.), and media devices (e.g., recorders, editors, televisions, set-top boxes, music players, digital photo frames, digital cameras, etc.).

In some aspects, the input device 100 may be implemented as a physical part of a corresponding electronic system. Alternatively, input device 100 may be physically separate from the electronic system. Input device 100 may be coupled to (and in communication with) components of an electronic system using various wired and/or wireless interconnections and communication techniques, such as buses and networks. Example suitable techniques may include inter-integrated circuit (I)²C) Serial Peripheral Interface (SPI), PS/2, Universal Serial Bus (USB), Bluetooth, Infrared data Association (IrDA), and the various Radio Frequency (RF) communication protocols defined by the IEEE 802.11 family of standards.

In the example of fig. 1, the input device 100 may correspond to a fingerprint sensor (also referred to as a "fingerprint scanner" or "fingerprint sensing apparatus") configured to sense input provided by input objects 140 in the sensing region 120. In some implementations, the input object 140 may correspond to a finger or fingertip of a user. The sensing region 120 may encompass any space above, around, in, and/or near the input device 100 where the input device 100 is capable of detecting user input. The size, shape, and/or positioning of the sensing region 120 may vary depending on the actual implementation. In some implementations, the sensing region 120 may extend from the surface of the input device 100 in one or more directions in space, for example, until the signal-to-noise ratio (SNR) of the sensor drops below a threshold suitable for fingerprint detection. For example, the distance to which the sensing region 120 extends in a particular direction may be approximately less than one millimeter, millimeters, centimeters, or more, and may vary with the type of sensing technology used and/or the accuracy desired.

Input device 100 may utilize various sensing techniques to detect user input. Example sensing technologies may include capacitive sensing technologies, optical sensing technologies, and ultrasonic sensing technologies. In some implementations, the sensing region 120 may be formed by an array of capacitive sensing elements (e.g., sensor electrodes) for measuring changes in capacitance produced by a finger interacting with the sensing region 120. For example, the sensing region 120 may include one or more capacitive sensing elements (e.g., sensor electrodes) to create an electric field. The input device 100 may detect an input based on a change in capacitance of the sensor electrode. For example, an object in contact with (or in close proximity to) the electric field may cause a change in voltage and/or current in the sensor electrodes. More specifically, changes in voltage and/or current at various points in the array may be related to ridges and valleys in the user's finger.

Example capacitive sensing techniques may be based on "self-capacitance" (also referred to as "absolute capacitance") and/or "mutual capacitance" (also referred to as "transcapacitive"). The absolute capacitance sensing method detects a change in capacitive coupling between a sensor electrode and an input object. For example, an input object near the sensor electrode may alter the electric field near the sensor electrode, thus changing the measured capacitive coupling. In some implementations, the input device 100 can enable absolute capacitive sensing by modulating the sensor electrodes relative to a reference voltage and detecting capacitive coupling between the sensor electrodes and an input object. The reference voltage may be substantially constant or may vary. In some aspects, the reference voltage may correspond to a ground potential.

The transcapacitive sensing method detects changes in capacitive coupling between sensor electrodes. For example, an input object near the sensor electrodes may alter the electric field between the sensor electrodes, thus changing the measured capacitive coupling of the sensor electrodes. In some implementations, input device 100 may enable transcapacitive sensing by detecting capacitive coupling between one or more "transmitter" electrodes and one or more "receiver" electrodes. The transmitter electrode may be modulated relative to the receiver electrode. For example, the transmitter electrode may be modulated relative to a reference voltage to transmit a signal, while the receiver electrode may be held at a relatively constant voltage to "receive" the transmitted signal. The signal received by the receiver electrode may be affected by environmental interference (e.g., from objects in contact with or in close proximity to the sensor electrode). In some aspects, each sensor electrode may be a dedicated transmitter or a dedicated receiver. In other aspects, each sensor electrode can be configured to transmit and receive.

The processing system 110 may be configured to operate the hardware of the input device 100 to detect input in the sensing region 120. In some implementations, the processing system 110 may control one or more sensor electrodes to detect objects and/or fingerprints in the sensing region 120. For example, the processing system 110 may be configured to transmit signals via one or more transmitter sensor electrodes and receive signals via one or more receiver sensor electrodes. In some aspects, one or more components of processing system 110 may be co-located, such as in close proximity to a sensing element of input device 100. In some other aspects, one or more components of processing system 110 may be physically separate from the sensing elements of input device 100. For example, the input device 100 may be a peripheral device coupled to a computing device, and the processing system 110 may be implemented as software executed by a Central Processing Unit (CPU) of the computing device. In another example, the input device 100 may be physically integrated in a mobile device, and the processing system 110 may correspond at least in part to a CPU of the mobile device.

Processing system 110 may be implemented as a collection of modules implemented in firmware, software, or a combination thereof. Example modules include a hardware operation module to operate hardware such as one or more sensing elements; a data processing module for processing data such as sensor signals; and a reporting module for reporting information to other components of the electronic system, such as a host processor or CPU. In some implementations, the processing system 110 can include a sensor manipulation module configured to manipulate the sensing elements to detect user input in the sensing region 120; an authentication module configured to authenticate a user of the input device 100 and/or electronic system based at least in part on the user input; a recognition module configured to recognize gestures associated with certain user inputs; and a mode change module for changing an operation mode of the input device 100 and/or the electronic system.

The processing system 110 may respond to user input in the sensing region 120 by triggering one or more actions. Example actions include changing an operating mode of input device 100 and/or authenticating a user of input device 100. In some implementations, the processing system 110 can provide information about the detected input to an electronic system (e.g., to a CPU of the electronic system). The electronic system may then process the information received from the processing system 110 to perform additional actions (e.g., change a mode of the electronic system and/or authenticate operations).

The processing system 110 may perform any suitable amount of processing on the electrical signals to convert or generate information that is provided to the electronic system. For example, the processing system 110 may digitize analog signals received via the sensor electrodes and/or perform filtering or conditioning on the received signals. In some aspects, the processing system 110 may subtract or otherwise account for a "baseline" associated with the sensor electrodes. For example, when no user input is detected, the baseline may represent the state of the sensor electrodes. Thus, the information provided to the electronic system by the processing system 110 may reflect the difference between the signals received from the sensor electrodes and the baseline associated with each sensor electrode.

In some implementations, the processing system 110 may scan the sensor electrodes to capture or acquire a capacitive "image" of the fingerprint 140 when the fingerprint 140 is placed on the sensing region 120 of the input surface. The change in capacitance across the image may be interpreted as a pattern of ridges and valleys in the user's fingertip (e.g., representing the user's fingerprint). The details and accuracy of the capacitive sensing information may be affected by the input surface through which the sensing signals are transmitted and received. For example, input surfaces made of thinner materials and/or having higher dielectric constants tend to produce more accurate sensed information. Therefore, some fingerprint sensors are manufactured by placing a very thin sheet of cover material (such as glass) on top of an open enclosure surrounding the capacitive sensing element. The cover sheet serves as an input surface while closing the housing and enclosing the sensing element therein. However, such multi-piece enclosure assemblies are typically fragile, expensive to manufacture, and provide limited customizability.

In some embodiments, the housing assembly for input device 100 may be made of a single layer of material and/or compound. For example, the material forming the housing assembly may have a non-uniform thickness, wherein the open area coinciding with the input surface is thinner than the surrounding area (e.g., which provides side support or the rest of the housing). The fingerprint sensor may be arranged within the open area such that the sensor electrodes are positioned just below the input surface. In some embodiments, the housing assembly may be molded from a polymeric material (such as plastic, mylar, etc.). The polymer material can be molded into a very thin input surface with a relatively high dielectric constant (e.g., higher than that of glass), allowing for robust capacitive sensing measurements. In contrast to existing multi-piece enclosure assemblies, the enclosure assembly of this embodiment may be produced by a single manufacturing (e.g., molding) process.

Fig. 2A and 2B illustrate an example sensor assembly 200 according to some embodiments. Specifically, fig. 2A shows an isometric view of sensor assembly 200, and fig. 2B shows a cross-sectional view of sensor assembly 200. In some implementations, the sensor assembly 200 can be one example of the input device 100 of fig. 1.

In the example of fig. 2A and 2B, the sensor assembly 200 is configured as a key cap structure that may be included or integrated with a keyboard or keypad, for example. The sensor assembly 200 includes a fingerprint sensor 204 and a cover layer 202 having a substantially flat surface 203. As shown in fig. 2B, the cover layer 202 is formed from a single layer of material (such as plastic, mylar, or polymer) having a non-uniform thickness. The fingerprint sensor 204 is disposed under the cover layer 202 in the open area where the material is thinnest. Thus, the flat surface 203 of the overlay 202 may provide an input surface for capturing or acquiring a fingerprint. For example, planar surface 203 may include sensing region 102 of fig. 1.

FIGS. 3A-3C illustrate cross-sectional views 300-320, respectively, of an example sensor assembly at various stages of a manufacturing process according to some embodiments. In some embodiments, the manufacturing process described with respect to fig. 3A-3C may be used to manufacture the sensor assembly 200 of fig. 2. Thus, the sensor assembly of fig. 3A-3C may correspond to a fingerprint sensor assembly. In some implementations, the sensor assembly can be configured as a keycap.

As shown in fig. 3A, the cover layer 302 may be molded from a first material. In some embodiments, the first material may be a polymer, such as, for example, plastic, mylar, or the like. Further, in some embodiments, the first material may be selected to have a relatively high dielectric constant. In some aspects, the first material may be opaque (e.g., colored). In some other aspects, the first material may be translucent. As shown in fig. 3A, the cover layer 302 has a substantially flat surface 304 and a non-uniform thickness. In some embodiments, the outer surface of the cover layer 302 may be colored (paint) for aesthetic purposes and/or to obscure circuitry disposed therein. In some other embodiments, text and/or images may be printed on the flat surface 304 to indicate the use or function of the sensor assembly. The thickness of the material in the open area 306 below the flat surface 304 (T1) may be substantially less (e.g., thinner) than the thickness of the material surrounding the open area 306 (T2). Thus, the open area 306 provides an opening or cavity in the cover layer 302 within which a sensor device may be disposed.

As shown in fig. 3B, a glue or adhesive 312 is dispensed into the open area 306 of the cover layer 302. More specifically, glue 312 may be used to bond the sensor device to the cover layer 302 on the underside of the planar surface 304. In some embodiments, the glue 312 may be a thermal type glue that may be cured or solidified using heat. In the example of fig. 3B, glue 312 is shown to fill the open area 306 of the cover layer 302. However, a smaller or larger amount of glue 312 may be used in other embodiments.

As shown in fig. 3C, the sensor device is disposed or inserted into the open area 306 of the cover layer 302. In some implementations, the sensor device can be a fingerprint sensor that includes an array of sensor electrodes 322 coupled to a Printed Circuit Board (PCB) 324. The sensor electrodes 322 may be configured to transmit and receive capacitive sensing signals for fingerprint detection. The PCB may include circuitry (such as one or more processors) for operating the sensor electrodes 322 and/or interpreting the capacitive sensing signals. Alternatively or additionally, the PCB 324 may include circuitry (such as pins, traces, etc.) for routing the capacitive sensing signals to and from an external processor or CPU. In some implementations, the sensor electrodes 322 may be stacked on top of the PCB 324. This allows the sensor electrodes 322 to be positioned in close proximity to the planar surface 304 and thus transmit and receive capacitive sensing signals through the planar surface 304 of the cover layer 302. With the sensor device properly positioned below the planar surface 304, the glue 312 may be heated or cured to bond and/or encapsulate the sensor device with the cover layer 302.

Fig. 4A and 4B illustrate another example sensor assembly 400 according to some embodiments. In particular, fig. 4A shows an isometric view of sensor assembly 400, and fig. 4B shows a cross-sectional view of sensor assembly 400. In some implementations, the sensor assembly 400 can be one example of the input device 100 of fig. 1. Furthermore, in some embodiments, the sensor assembly 400 may be manufactured using the processes described with respect to fig. 3A-3C.

The sensor assembly 400 includes a fingerprint sensor 404 and an overlay 402 having a substantially planar surface 403. In the example of fig. 4A and 4B, the cover 402 is formed from a single layer of material (such as plastic, mylar, or polymer) having a non-uniform thickness. More specifically, overlay 402 is molded to include a raised or contoured edge around the perimeter or boundary of planar surface 403. The fingerprint sensor 404 is disposed under the cover 404 in an open area where the material is thinnest. Thus, the flat surface 403 of overlay 402 may provide an input surface for capturing or taking a fingerprint, and the wavy edges may serve as guides for placing a user's finger.

Fig. 5A and 5B illustrate another example sensor assembly 500 according to some embodiments. Specifically, fig. 5A shows a top view of sensor assembly 500, and fig. 5B shows a cross-sectional view of sensor assembly 500. In some implementations, the sensor assembly 500 may be one example of the input device 100 of fig. 1. Furthermore, in some embodiments, the sensor assembly 500 may be manufactured using the processes described with respect to fig. 3A-3C.

As shown in fig. 5A, the sensor assembly 500 includes an overlay 510 configured to emit or emit light via a ring of light 512. In some embodiments, cover layer 510 may be molded from a translucent material capable of transmitting light, such as plastic, mylar, or a polymer. The surface 514 surrounded by the light rings 512 may be tinted to confine or position the emitted light to the uncolored areas forming the light rings 512. As shown in fig. 5B, the sensor assembly 500 further includes a fingerprint sensor 520 disposed below the overlay 510 and one or more light sources 530 disposed below the sensor 520. In some embodiments, light source 530 may include a Light Emitting Diode (LED) or any other light source capable of emitting light in the visible spectrum. In some implementations, the light source 530 can be coupled to the fingerprint sensor 520. For example, the light source 530 may be configured to emit light in a particular pattern and/or color to indicate the status or configuration of the fingerprint sensor 520. In some implementations, the sensor assembly 500 can further include one or more light guides 540 to help guide light emitted by the light sources 530 to the light rings 512 in the cover layer 510.

Fig. 6A and 6B illustrate another example sensor assembly 600 according to some embodiments. In particular, fig. 6A shows a top view of sensor assembly 600, and fig. 6B shows a cross-sectional view of sensor assembly 600. In some implementations, the sensor assembly 600 may be one example of the input device 100 of fig. 1. Furthermore, in some embodiments, sensor assembly 600 may be manufactured using the processes described with respect to fig. 3A-3C.

As shown in fig. 6A, the sensor assembly 600 includes a cover layer 610 configured to emit or emit light via a light bar 612. In some embodiments, cover layer 610 may be molded from a translucent material capable of transmitting light, such as plastic, mylar, or a polymer. The surface 614 surrounding the light bar 612 may be colored to confine or position the emitted light to uncolored regions forming the light bar 612. As shown in fig. 6B, the sensor assembly 600 further includes a fingerprint sensor 620 disposed below the overlay 610 and one or more light sources 630 disposed below the sensor 620. In some embodiments, light source 630 may include an LED or any other light source capable of emitting light in the visible spectrum, the IR spectrum, or the UV spectrum. In some implementations, the light source 630 can be coupled to the fingerprint sensor 620. For example, the light source 630 may be configured to emit a particular pattern and/or color of light to indicate the status or configuration of the fingerprint sensor 620.

FIG. 7 illustrates another example input device 700 that may be used with the present embodiments. The input device 700 includes a processing system 710 and a sensing region 720. Input device 700 may be configured to provide input to an electronic system (not shown for simplicity). Examples of electronic systems may include personal computing devices (e.g., desktop computers, laptop computers, netbook computers, tablet computers, web browsers, e-book readers, and PDAs), composite input devices (e.g., physical keyboards, joysticks, and key switches), data input devices (e.g., remote controls and mice), data output devices (e.g., display screens and printers), remote terminals, kiosks, video game consoles (e.g., video game consoles, portable game devices, etc.), communication devices (e.g., cellular telephones such as smart phones), and media devices (e.g., recorders, editors, and players, such as televisions, set-top boxes, music players, digital photo frames, and digital cameras).

In some aspects, the input device 700 may be implemented as a physical part of a corresponding electronic system. Alternatively, the input device 700 may be physically separate from the electronic system. Input device 700 may be coupled to (and communicate with) components of an electronic system using various wired and/or wireless interconnections and communication techniques, such as buses and networks. Example techniques may include I²C. SPI, PS/2, USB, Bluetooth, IrDA, and the various RF communication protocols defined by the IEEE 802.11 family of standards.

In the example of fig. 7, input device 700 may correspond to a proximity sensor device (e.g., also referred to as a "touchpad" or a "touch sensor device") configured to sense input provided by one or more input objects 740 in sensing region 720. Example input objects 740 include a finger, a stylus, and the like. Sensing region 720 may encompass any space above, around, in, and/or near input device 700 in which input device 700 is capable of detecting user input (such as provided by one or more input objects 740). The size, shape, and/or positioning of sensing region 720 (e.g., relative to an electronic system) may vary depending on the actual implementation.

In some implementations, sensing region 720 may extend from a surface of input device 700 in one or more directions in space, for example, until the SNR of the sensor drops below a threshold suitable for object detection. For example, the distance to which sensing region 720 extends in a particular direction may be approximately less than one millimeter, millimeters, centimeters, or more, and may vary with the type of sensing technology used and/or the accuracy desired. In some implementations, sensing region 720 may detect input relating to: no physical contact with any surface of input device 700, contact with an input surface (e.g., a touch surface and/or a screen) of input device 700, contact with an input surface of input device 700 coupled with an amount of applied force or pressure, and/or any combination thereof.

In some implementations, the input surface may be provided by and/or projected (e.g., as an image) on one or more surfaces of the housing of the input device 700. For example, sensing region 720 may have a rectangular shape when projected onto an input surface of input device 700. In some aspects, input may be provided by images spanning a one-, two-, three-, or higher-dimensional space in sensing region 720. In some other aspects, input may be provided by projection along a particular axis or plane in sensing region 720. Further, in some aspects, input may be provided by a combination of images and projections in sensing region 720.

The input device 700 may utilize various sensing techniques to detect user input. Example sensing technologies may include capacitive, inverted dielectric, resistive, inductive, magnetic, acoustic, ultrasonic, thermal, and optical sensing technologies. In some implementations, the input device 700 can utilize capacitive sensing techniques to detect user input. For example, sensing region 720 may include one or more capacitive sensing elements (e.g., sensor electrodes) to create an electric field. The input device 700 may detect an input based on a change in capacitance of the sensor electrodes. For example, an object in contact with (or in close proximity to) the electric field may cause a change in voltage and/or current in the sensor electrodes. Such a change in voltage and/or current may be detected as a "signal" indicative of a user input. The sensor electrodes may be arranged in an array or other configuration to detect input at multiple points within sensing region 720. As described above, example capacitive sensing techniques may be based on absolute capacitance and/or transcapacitance.

The processing system 710 may be configured to operate the hardware of the input device 700 to detect input in the sensing region 720. In some implementations, processing system 710 may control one or more sensor electrodes to detect objects in sensing region 720. For example, processing system 710 may be configured to transmit signals via one or more transmitter sensor electrodes and receive signals via one or more receiver sensor electrodes. In some aspects, one or more components of processing system 710 may be co-located, for example, in close proximity to a sensing element of input device 700. In some other aspects, one or more components of the processing system 710 may be physically separate from the sensing elements of the input device 700. For example, the input device 700 may be a peripheral device coupled to a computing device, and the processing system 710 may be implemented as software executed by a CPU of the computing device. In another example, the input device 700 may be physically integrated in a mobile device, and the processing system 720 may correspond at least in part to a CPU of the mobile device.

In some implementations, the processing system 710 may be implemented as a collection of modules implemented in firmware, software, or a combination thereof. Example modules include hardware operation modules for operating hardware such as sensor electrodes and display screens; a data processing module for processing data such as sensor signals and position information; and a reporting module for reporting the information. In some implementations, the processing system 710 may include a sensor operation module configured to operate the sensing elements to detect user input in the sensing region 720; a recognition module configured to recognize a gesture, such as a mode change gesture; and a mode change module for changing an operation mode of the input device 700 and/or the electronic system.

Input device 700 may include additional input components that may be operated by processing system 710 or another processing system. In some embodiments, the additional input components may include a fingerprint sensor that may be used to authenticate the user of the input device 700 and/or the corresponding electronic system. For example, the fingerprint sensor may use capacitive fingerprint imaging techniques to detect and/or analyze a user's fingerprint 730 in the fingerprint scan area 750. In some embodiments, the fingerprint scanning area 750 may coincide or substantially overlap with the sensing area 720.

Processing system 710 may respond to user input in sensing region 720 and/or fingerprint scanning region 750 by triggering one or more actions. Example actions include changing an operating mode of input device 700 and/or Graphical User Interface (GUI) actions such as cursor movement, selection, menu navigation, and the like. In some implementations, the processing system 710 may determine location information of the detected input. As used herein, the term "positional information" refers to any information that describes or otherwise indicates the location or position of detected input (e.g., within sensing region 720). Example location information may include absolute location, relative location, velocity, acceleration, and/or other types of spatial information. In some implementations, the processing system 710 can provide information about the detected input to an electronic system (e.g., to a CPU of the electronic system). The electronic system may then process the information received from the processing system 710 to perform additional actions (e.g., changing a mode of the electronic system and/or GUI actions).

The processing system 710 may operate the sensing elements of the input device 700 to generate electrical signals indicative of input (or lack thereof) in the sensing region 720 and/or the fingerprint scanning region 750. The processing system 710 may perform any suitable amount of processing on the electrical signals to convert or generate information that is provided to the electronic system. For example, processing system 710 may digitize analog signals received via the sensor electrodes and/or perform filtering or conditioning on the received signals. In some aspects, processing system 710 may subtract or otherwise account for a "baseline" associated with the sensor electrodes. For example, when no user input is detected, the baseline may represent the state of the sensor electrodes. Thus, the information provided to the electronic system by processing system 710 may reflect the difference between the signals received from the sensor electrodes and the baseline associated with each sensor electrode.

In some implementations, the processing system 710 may interpret the location information based on user input received at least in part via the fingerprint scan area 750. For example, the location information may correspond to a swipe gesture initiated in the sensing region 720 and crossing or terminating in the fingerprint scanning region 750. Aspects of the present disclosure recognize that it may be desirable to interpret such user input as gesture input rather than fingerprint input. However, in some input devices, the input surface associated with the scanning region 750 is disposed in a cutout window of the input surface associated with the sensing region 720. In other words, the fingerprint sensor (under the fingerprint scanning area 750) and the proximity sensor (under the sensing area 720) have different input surfaces that are separately manufactured and combined at the assembly stage. Thus, there is a gap or opening at the transition or intersection of the fingerprint scanning region 750 and the sensing region 720. Such gaps may create "dead zones" in sensing region 720 and/or fingerprint scan region 750 due to poor sensitivity and/or user experience.

In some implementations, the shared input surface for the sensing region 720 and the fingerprint scanning region 750 may be created from a single layer of material and/or compound. For example, the material forming the input surface may have a non-uniform thickness, wherein the area of the opening coinciding with the input surface is thinner than the surrounding area. The fingerprint sensor may be arranged within the open area such that the sensor electrodes are located directly below the input surface. The proximity sensor may be disposed below a region of the input surface surrounding the open area. In some embodiments, the input surface may be molded from a polymeric material (such as plastic, mylar, etc.). The polymer material can be molded into a very thin input surface with a relatively high dielectric constant (e.g., higher than that of glass), allowing for robust capacitive sensing measurements. In contrast to existing input devices having multiple input surfaces, the input surface of the present embodiment may be produced by a single manufacturing (e.g., molding) process.

Fig. 8A and 8B illustrate another example sensor assembly 800 according to some embodiments. In particular, fig. 8A shows an isometric view of sensor assembly 800, and fig. 8B shows a cross-sectional view of sensor assembly 800 (e.g., the upper right corner of sensor assembly 800). In some implementations, the sensor assembly 800 may be one example of the input device 700 of fig. 7.

In the example of fig. 8A and 8B, the sensor assembly 800 is configured as a touchpad or trackpad, for example, which may be included or integrated with a keyboard or keypad. The sensor assembly 800 includes a fingerprint sensor 820, a proximity sensor 830, and a cover 810 having a substantially flat surface 801. As shown in fig. 8B, the cover layer 810 is formed of a single layer of material (such as plastic, mylar, or polymer) having a non-uniform thickness. The fingerprint sensor 820 is placed under the cover layer 810 in the open area 814 where the material is thinnest. A proximity sensor 830 is also disposed beneath the cover 810 in a region 812 surrounding the open area 814. In some implementations, the fingerprint sensor 820 can be coupled to the proximity sensor 830 via a PCB 832 (also referred to as a "proximity sensor PCB") associated with the proximity sensor 830. Still further, in some embodiments, the underside 816 of the cover layer 810 may be colored for aesthetic purposes (e.g., to provide a glass or mirror-like finish) and/or to hide underlying circuitry.

The flat surface 801 of the overlay 810 may provide a continuous or uninterrupted input surface for detecting fingerprints and proximity information from one or more input objects. Referring to, for example, fig. 7, a flat surface 801 may encompass the sensing region 720 and the fingerprint scanning region 750. More specifically, the fingerprint scanning area 750 may coincide with the open area 814 of the cover layer 810, and the sensing area 720 may coincide with the surrounding area 812 of the cover layer 810. Because there are no openings or gaps at the transitions or intersections between the open area 814 and the surrounding area 812, the sensor assembly 800 may provide improved performance and/or user experience compared to prior input devices having multiple input surfaces.

FIGS. 9A-9F illustrate cross-sectional views 900-950, respectively, of another example sensor assembly at various stages of a manufacturing process, according to some embodiments. In some embodiments, the manufacturing process described with respect to fig. 9A-9F may be used to manufacture the sensor assembly 800 of fig. 8. Thus, the sensor assemblies of fig. 9A-9F may correspond to a combined fingerprint and proximity sensor assembly. In some implementations, the sensor assembly can be configured as a touchpad or a trackpad.

As shown in fig. 9A, the fingerprint sensor 904 is placed in a cavity or opening of the fixture 902. Although not shown, for simplicity, the fingerprint sensor 904 may include an array of sensor electrodes coupled to a PCB. The sensor electrodes may be configured to transmit and receive capacitive sensing signals for fingerprint detection. The PCB may comprise circuitry for operating the sensor electrodes and/or interpreting the capacitive sensing signal. Alternatively or additionally, the PCB may comprise circuitry for routing the capacitive sensing signal to and from an external processor or CPU. In some implementations, the PCB can be stacked on top of the sensor electrodes such that the sensor electrodes face or are adjacent to the fixture 902. This will allow the sensor electrodes to be positioned in close proximity to the cover layer to be added at a later stage of the manufacturing process.

As shown in fig. 9B, a proximity sensor PCB 912 may be placed on top of the fixture 902, surrounding the fingerprint sensor 904. The proximity sensor PCB 912 may be coupled to or include one or more sensor electrodes (not shown for simplicity) configured to transmit and receive capacitive sensing signals for proximity detection. The proximity sensor PCB 912 may include circuitry for operating the sensor electrodes and/or interpreting the capacitive sensing signals. Alternatively or additionally, the proximity sensor PCB 912 may include circuitry for routing the capacitive sensing signal to an external processor CPU. In some implementations, the proximity sensor PCB 912 can further provide a communication interface between the fingerprint sensor 904 and the proximity sensor.

As shown in fig. 9C, the proximity sensor PCB 912 is wire bonded to the fingerprint sensor 904. More specifically, the fingerprint sensor 904 may be coupled to the proximity sensor PCB 912 via one or more leads 922. Aspects of the present disclosure recognize that wire bonding (e.g., as compared to conventional solder flow processes) is a relatively low cost technique for coupling the fingerprint sensor 904 to the proximity sensor PCB 912. Unlike solder balls, however, leads 922 may need to be packaged or otherwise protected from external elements.

As shown in fig. 9D, an epoxy molding compound or other filler material (such as silicone) 932 is dispensed into the openings of the fixture 902. An epoxy molding compound 932 may be used to encapsulate and/or hold leads 922 in place. For example, once cured, the epoxy mold compound 932 may prevent the leads 922 from bending or separating under external forces and/or stresses. In some embodiments, the epoxy molding compound 932 may be opaque. In some other embodiments, the epoxy molding compound 932 may be translucent.

As shown in fig. 9E, after the epoxy molding compound 932 is cured, the fixture 902 is removed. The glue 944 is dispensed on a surface of the fingerprint sensor 904 (e.g., a surface adjacent to the fixture 902) and one or more adhesives 942 is attached to a surface of the proximity sensor PCB 912 (e.g., a surface adjacent to the fixture 902). In some embodiments, the glue 944 may be a thermal type glue that can be cured or solidified using heat.

As shown in fig. 9F, a cover layer 952 is placed over the sensor assembly and is bonded or attached to the fingerprint sensor 904 and the proximity sensor PCB 912 via glue 944 and adhesive 942, respectively. In some embodiments, the cover layer 952 may be molded from a polymeric material, such as, for example, plastic, mylar, or the like. Furthermore, in some embodiments, the material may be selected to have a relatively high dielectric constant. In some aspects, the material may be opaque (e.g., colored). In some other aspects, the material may be translucent. As shown in fig. 9F, the cover layer 952 has a substantially flat surface 951 and a non-uniform thickness. In some embodiments, the underside of the cover layer 952 (e.g., opposite the flat surface 951) may be colored to provide a glass-like or mirror-like finish and/or to obscure circuitry disposed underneath. The thickness of the material in the region coinciding with the fingerprint sensor 904 may be less (e.g., thinner) than the thickness of the material coinciding with the proximity sensor PCB 912. Thus, the fingerprint sensor 904 may be positioned closer to the flat surface 951 than the proximity sensor PCB 912.

FIG. 10 shows an illustrative flow diagram of a process 1000 for manufacturing a sensor assembly, according to some embodiments. More specifically, process 1000 may be used to manufacture any of the example sensor assemblies described herein.

The first material is molded to form a cover layer having a flat surface and a non-uniform thickness (1010). The first material may be a polymer, such as plastic, mylar, or the like. In some aspects, the first material may be selected to have a relatively high dielectric constant. The first material may be thinner in a first region of the cover layer below the planar surface and thicker in a region surrounding the first region. In some embodiments, the overlay layer may be molded to form a housing for the fingerprint sensor (such as described with respect to fig. 1-6B). In some other embodiments, the overlay layer may be molded to form a composite input surface for multiple sensor devices (such as described with respect to fig. 7-9F).

In the first region, a first sensor arrangement (1020) is arranged below the flat surface of the cover layer. The first sensor arrangement may be configured to transmit and receive capacitive sensing signals through a portion of the planar surface coinciding with the first area. In some embodiments, the first sensor arrangement may be a fingerprint sensor configured to detect a fingerprint on a flat surface using capacitive sensing technology. Thus, the first sensor device may be positioned below the thinnest area of the cover layer such that the associated sensor electrode is closest to the flat surface (such as described with respect to fig. 3C and 9F).

In some embodiments, a second sensor device (1030) is disposed below the planar surface of the cover layer in a second region surrounding the first region. The second sensor arrangement may be configured to transmit and receive capacitive sensing signals through a portion of the planar surface coinciding with the second region. In some embodiments, the second sensor device may be a proximity sensor configured to determine positional information of an object on or near the flat surface using capacitive sensing techniques. However, because the location information may be finer grained or accurate than the capacitive sensor data required for fingerprint detection and authentication, the second sensor device may be positioned under a thicker region of the overlay layer such that the associated sensor electrodes are farther from the flat surface than the sensor electrodes used for fingerprint detection (such as described with respect to fig. 9F).

Those of skill in the art would understand that information and signals may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

Furthermore, those of skill in the art will appreciate that the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the aspects disclosed herein may be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present disclosure.

The methods, sequences or algorithms described in connection with the aspects disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor.

In the foregoing specification, embodiments have been described with reference to specific examples thereof. It will, however, be evident that various modifications and changes may be made thereto without departing from the broader scope of the disclosure as set forth in the appended claims. The specification and drawings are, accordingly, to be regarded in an illustrative sense rather than a restrictive sense.

Claims

1. A sensor assembly comprising:

A cover layer molded from a first material to have a flat surface and a non-uniform thickness, wherein the thickness of the first material at a first region of the cover layer is less than the thickness of the first material surrounding the first region the thickness of the material; and

a first sensor device disposed in the first region below the flat surface of the cover layer, the first sensor device being configured to pass through the flat surface coinciding with the first region portion of the surface to transmit and receive the first capacitive sensing signal.

2. The sensor assembly of claim 1, wherein the first material comprises plastic, mylar, epoxy molding compound, or a polymer.

3. The sensor assembly of claim 1, wherein the first sensor device comprises a fingerprint sensor configured to detect coincidence with the first region based on a change in the first capacitive sensing signal of fingerprints on said portion of said flat surface.

4. The sensor assembly of claim 1, wherein the first sensor device is bonded to the first region of the cover layer using glue.

5. The sensor assembly of claim 1, further comprising:

A second sensor arrangement disposed below the flat surface of the cover layer in a second region surrounding the first region, the second sensor arrangement being configured to coincide with the second region by portion of the flat surface to transmit and receive second capacitive sensing signals.

6. The sensor assembly of claim 5, wherein the second sensor arrangement comprises a proximity sensor configured to detect relative to the input object relative to the The second zone coincides with the location of the portion of the flat surface.

7. The sensor assembly of claim 5, wherein the second sensor device is bonded to the second region of the cover layer using an adhesive.

8. The sensor assembly of claim 5, wherein the second sensor device is coupled to the first sensor device via wire bonds.

9. The sensor assembly of claim 8, wherein the wire bonds are encapsulated in a sealing material disposed between the first sensor device and the second sensor device.

10. The sensor assembly of claim 1, wherein an underside of the cover layer is colored a first color, wherein the underside of the cover layer is opposite the flat surface.

11. A sensor assembly comprising:

a cover layer molded from a first material to have a flat surface and a non-uniform thickness, wherein the thickness of the first material at a first region of the cover layer is less than the thickness of the first material surrounding the first region the thickness of the material;

a fingerprint sensor disposed in the first zone below the flat surface of the cover layer, the fingerprint sensor configured to detect on a portion of the flat surface that coincides with the first zone fingerprints; and

a proximity sensor disposed below the flat surface of the overlay in a second zone surrounding the first zone, the proximity sensor configured to detect an input object relative to coincident with the second zone the position of the portion of the flat surface.